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Moura E.F.,Embrapa Amazonia Oriental
Genetics and molecular research : GMR | Year: 2012

Oenocarpus mapora is an Amazonian palm species commonly used by native populations for food and in folk medicine. We measured genetic variability, using RAPD markers, of material kept in a germplasm bank composed of accessions sampled from the Brazilian Amazon. These included 74 individuals from 23 accessions sampled from 9 localities in three States of the Brazilian Amazon. Jaccard genetic similarities were calculated based on 137 polymorphic bands, amplified by 15 primers. Dendrograms constructed based on the genetic similarities among individuals and sample localities demonstrated genetic separation of Acre State from the States of Amazonas and Pará. Two models in three hierarchical levels were considered for AMOVA: one considering the grouping of sampling sites in each state, and the other considering sampling sites in each subgroup formed by the dendrograms. The first model showed no significant genetic variation among states. On the other hand, genetic variation among subgroups was significant. In this model, the within-sample-site genetic diversity was 47.15%, which is considered to be low, since O. mapora is allogamous. By means of Bayesian analysis, the sample sites were clustered into five groups, and their distribution was similar to what we found in the dendrograms based on genetic similarity.

Flechtmann C.H.W.,University of Sao Paulo | Noronha A.C.S.,Embrapa Amazonia Oriental
Systematic and Applied Acarology | Year: 2011

Tetranychus palmarum sp.nov., a new red spider mite from the African oil palm, is described and figured. © 2011 Systematic & Applied Acarology Society.

Freitas D.G.C.,Embrapa Agroindustria de Alimentos | Mattietto R.A.,Embrapa Amazonia Oriental
Food Science and Technology | Year: 2013

Ready-to-drink fruit juices represent a large share of the market and are an important target for product development. The mixture of fruits can bring about improvements to nutritional and sensory aspects of these beverages while making used of the wide variety of exotic fruits from the Amazon region. Therefore, it is necessary to select mixed fruits and determine their ideal sweetness according to consumer acceptance. Consumers in the city of Belém (Brazil) evaluated five different concentrations of sugar using the just-about-right scale in two blends selected by preference ranking. For the cupuassu-acerola-açai blend, the optimum concentration of sugar was 9.5 g/100 mL, and for the soursop-camucamu-yellow mombin blend, it was 10.7 g/100 mL.

Berenguer E.,Lancaster University | Ferreira J.,Embrapa Amazonia Oriental | Gardner T.A.,University of Cambridge | Gardner T.A.,International Institute for Sustainability | And 9 more authors.
Global Change Biology | Year: 2014

Tropical rainforests store enormous amounts of carbon, the protection of which represents a vital component of efforts to mitigate global climate change. Currently, tropical forest conservation, science, policies, and climate mitigation actions focus predominantly on reducing carbon emissions from deforestation alone. However, every year vast areas of the humid tropics are disturbed by selective logging, understory fires, and habitat fragmentation. There is an urgent need to understand the effect of such disturbances on carbon stocks, and how stocks in disturbed forests compare to those found in undisturbed primary forests as well as in regenerating secondary forests. Here, we present the results of the largest field study to date on the impacts of human disturbances on above and belowground carbon stocks in tropical forests. Live vegetation, the largest carbon pool, was extremely sensitive to disturbance: forests that experienced both selective logging and understory fires stored, on average, 40% less aboveground carbon than undisturbed forests and were structurally similar to secondary forests. Edge effects also played an important role in explaining variability in aboveground carbon stocks of disturbed forests. Results indicate a potential rapid recovery of the dead wood and litter carbon pools, while soil stocks (0-30 cm) appeared to be resistant to the effects of logging and fire. Carbon loss and subsequent emissions due to human disturbances remain largely unaccounted for in greenhouse gas inventories, but by comparing our estimates of depleted carbon stocks in disturbed forests with Brazilian government assessments of the total forest area annually disturbed in the Amazon, we show that these emissions could represent up to 40% of the carbon loss from deforestation in the region. We conclude that conservation programs aiming to ensure the long-term permanence of forest carbon stocks, such as REDD+, will remain limited in their success unless they effectively avoid degradation as well as deforestation. © 2014 The Authors.

Sist P.,CIRAD - Agricultural Research for Development | Mazzei L.,Embrapa Amazonia Oriental | Blanc L.,CIRAD - Agricultural Research for Development | Rutishauser E.,Carboforexpert
Forest Ecology and Management | Year: 2014

The long term effect of Reduced-Impact Logging (RIL) on above-ground live biomass (AGB) dynamics was investigated in 18 1-ha logged over permanent sample plots set up in a terra firme rain forest in the Eastern Amazon (Brazil, Paragominas). Both tree survival and growth were investigated among three Diameter at Breath Height (DBH) classes (20-40, 40-60, ≥60cm) to assess the contribution of each DBH class to the post-logging AGB recovery. Before logging, mean tree density and AGB per plot (dbh≥20cm) were 187±14 trees ha-1 and 377.6±62.8Mgha-1 respectively. Although big trees (dbh≥60cm) only represented 9.3% of the total tree density, they gathered almost half of total AGB. During the post-logging period (8years), the mortality of large trees was found to drive the annual net changes and largely overcame the AGB gain in the smaller DBH classes. Indeed, plots with high post-logging mortality of large trees showed negative carbon balance t over the study period (8years). The over mortality of large trees injured by logging contributed significantly to the annual AGB losses (up to 40%) in the first years after logging. Due to the overwhelming importance of this size class in carbon stocks and dynamic, reducing logging damages and intensity might have great impact in the post-logging biomass dynamics. We estimated that reducing logging intensity from 6 to 3 stems ha-1 would save 27.7Mg C ha-1 for a 35years rotation cycle. To compensate this loss of profits, compensatory payments of avoided CO2 emission should worth US $ 6.5/Mg of CO2. This price falls into the range of prices of the international carbon market. Sustainable forest management aiming at enhancing carbon stocks could therefore promote the preservation of the large trees. At our study site, we recommend the adoption of a maximum diameter cutting limit of 110cm. © 2014 Elsevier B.V.

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